<%@page import="java.sql.*"%>
<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>查询结果</title>
<style type="text/css">
h1{ color: red;}
.sql{font-weight: bold;}
.first{color:red;}
</style>
</head>
<body>
<h1>根据首字查成语</h1><% 
String first=request.getParameter("first");//获取用户输入的首字
if(first==null || first.trim().length()!=1){
	out.println("请正确输入一个汉字~");
	return;
}
String sql="select * from chengyu where first=?"; %>
<p class='sql'><%=sql%></p>
<p>以【<span class='first'><%=first%></span>】字开头的成语有：</p>
<% 

Class.forName("com.mysql.cj.jdbc.Driver");
try(Connection cn=DriverManager.getConnection("jdbc:mysql://localhost:3306/db?allowMultiQueries=true", "root", "12qwas");
		PreparedStatement ps=cn.prepareStatement(sql)){
	ps.setString(1, first);
	try(ResultSet rs=ps.executeQuery()){
		while(rs.next()){
			String cy=rs.getString("cy");
			out.println(cy+" ");
		}
	}
}
%>
</body>
</html>